Anything that is blended will be sub-standard compared to 100% synthetic. Why? Because, you could blend in a teaspoon of synthetic per quart and call it a "synthetic-blend"... I have been using ValvolinePremiumBlueExtreme for the last few years and it is great. What led me to that particular synthetic was the fact that Cummins did all of the beta-testing for Valvoline and came to the conclusion that they liked it so much that they made a deal w/ Valvoline to put the Cummins logo on the packaging. Now, you could say that is marketing. Fine, but the Cummins name and reputation is an outstanding one. So, if you should try it, make sure you get the "Extreme". Because that is 100% synthetic.
Here's a link w/ some info.
Extreme Engine Oil